Altered Signal Intensity Research Articles

Amendment on brain signal intensity on Magnetic Resonance Imaging of asymptomatic HTLV-1 seropositive and HTLV-1 associated myelopathy

HTLV-1-associated myelopathy (HAM) is a classic neurological disease, but cognitive impairment and altered signal intensity on MRI scans of the brain are described in the literature and suggest a more extensive neurological damage. This is a cross-sectional study, conducted between March 17th and September 28th, 2012 in the GIPH cohort, Brazil. HAM was diagnosed on the basis of the World Health Organization diagnostic clinical criteria. MRIs of the brain axial in T1-weighted Flair, fast spin-echo T2-weighted fat-suppressed, T2-weighted Flair and diffusion weighted EPI were performed. Blinded interpretation of MRIs was performed by radiologists who did not know clinical neurologic status of the participants. Fazekas scale (0-4) was used to classify the changes in brain signal intensity. In the 120 participants the mean age of the group was 48.0 ± 12.8 years (range: 16.4 to 72.6 years), no statistically significant difference between the mean ages of the HAM and asymptomatic groups (p = 0.7). Women were 77 (64.2%) of patients and HAM was diagnosed in 19 (15.8%). Change of signal intensity at MRIs was observed in 48 (47%) asymptomatic group and 11 (57%) HAM group (p = 0.4). Both groups showed Fazekas evaluation from 0 until 3, without statistically significant differences between them (p > 0.05). The alteration of signal intensity on MRIs of the brain of individuals HTLV-1 seropositive asymptomatic and with HAM were not statistically significant. As a continuation of this study, we are going to compare these findings with a group of controls without HTLV-1 infection.

Cartilage degeneration at symptomatic persistent olecranon physis in adolescent baseball players.

Background. Elbow overuse injuries are common in adolescent baseball players, but symptomatic persistent olecranon physis is rare, and its pathogenesis remains unclear. Purpose. To examine the histopathological and imaging findings of advanced persistent olecranon physis. Methods. The olecranon physes of 2 baseball pitchers, aged 14 and 15 years, were examined by preoperative magnetic resonance imaging (MRI), and surgical specimens were examined histologically. Results. T2-weighted MRI revealed alterations in the intrachondral signal intensity possibly related to collagen degeneration and increased free water content. Histological findings of specimens stained with hematoxylin-eosin showed complete disorganization of the cartilage structure, hypocellularity, chondrocyte cluster formation, and moderately reduced staining. All these findings are hallmarks of osteoarthritis and are suggestive of cartilage degeneration. Conclusion. Growth plate degeneration was evident in advanced cases of symptomatic persistent olecranon physis. These findings contribute to understanding the pathogenesis of this disease.

Hirayama Disease: Imaging Profile of Three Cases Emphasizing the Role of Flexion MRI

We report three cases of Hirayama disease, cervical flexion myelopathy presenting as unilateral or bilateral asymmetric muscular atrophy of forearm and hand involving C7 - T1 myotomes in young males. MRI revealed asymmetric cord atrophy, altered signal intensity of cord, posterior dural detachment and enlarged posterior epidural space with multiple flow voids. This article emphasizes the role of Flexion MRI in diagnosing Hirayama disease.

Cutting the edge of idiopathic recurrent orbital myositis

Abstract The spectrum of orbital inflammatory diseases ranges broadly from specific diseases as connective tissue disorders, thyroid ophthalmopathy to non-specific inflammations, which may involve one or multiple structures of the orbit and/ or the surrounding sinus. Idiopathic orbital myositis (IOM) may be a localized process or it can be secondary to systemic diseases. We report 4 patients affected by IOM; in all relapsing diplopia was the main complaint, associated with orbital pain in 3 and with abnormal visual evoked responses in 2. Computed tomography (CT), magnetic resonance imaging (MRI) supported the diagnosis revealing enlargement, altered signal intensity of affected muscles. Repeated MRI scans and extensive laboratory examinations comprising of the search for a remote malignacy, lymproliferative, connective tissue diseases, thyroid ophthalmopathy were necessary to confirm the diagnosis. Oral or/and intravenous steroids were main treatments; relapses often occurred when steroid was tapered down. Intravenous immuneglobulins and azathioprine was used in one refractory case

New REMPI observations and analyses for Rydberg and ion-pair states of HI

Two-dimensional REMPI data, obtained by recording ion mass spectra for HI as a function of two-photon wavenumber were recorded and analyzed. Several previously observed spectra due to resonance transitions to Ω=0 states were (re)assigned. The spectral data revealed several previously unobserved (2+n) REMPI spectra. These were assigned and analyzed to derive band origins and rotational parameters of Rydberg and ion-pair states. Perturbation effects, showing as line-shifts and/or signal intensity alterations, were found to be helpful in spectra assignments.

Accuracy of Transcranial Ultrasound in the Detection of Mild White Matter Lesions in Newborns

Cranial Ultrasound (cUS) may not be sensitive enough to detect subtle white matter (WM) injuries. Our study compared serial cUS with MRI at term equivalent age (TEA) to determine if it is possible to identify an ultrasound representation of subtle diffuse WM injuries such as punctate lesions (PWMLs) and diffuse excessive high signal intensity (DEHSI). Fifty-six very preterm infants were scanned sequentially from birth to TEA, an MRI was performed at TEA. Each echodensity found on cUS was classified as absent, transient (≤7 days), or prolonged (>7 days). A transient periventricular echodensity was detected in seven infants (12.5%), and a prolonged echodensity in 15 (26.8%). MRI examinations were performed in all 56 infants. No altered signal intensity was found in 18 infants (32.1%). DEHSI was detected in 14 infants (25%), and PWMLs were detected in eight babies (14.3%). Both abnormalities were found in 16 infants (28.6%). The positive predictive values of the prolonged echodensity for DEHSI and PWMLs were 86.7% and 46.7% respectively. However, a significant statistical correspondence (p=0.002, Odds Ratio 11.9) was found comparing DEHSI with cUS abnormal echodensities. Serial cUS during the neonatal period in preterm infants is essential and cannot be replaced with MRI at TEA. MRI seems to be more reliable in detecting mild or moderate WM abnormalities. However, serial cUS performed by an experienced neonatologist can provide valuable information on early WM changes such as prolonged echodensities that could potentially lead to a diffuse injury.

English

Thyroid-associated orbitopathy (TAO), frequently termed Graves ophthalmopathy, is part of an autoimmune process that can affect the orbital and periorbital tissue, the thyroid gland, and, rarely, the pretibial skin or digits (thyroid acropachy), Although the use of the term thyroid ophthalmopathy is pervasive, the disease process is actually an orbitopathy in which the orbital and periocular soft tissues are primarily affected with secondary effects on the eye. Thyroid orbitopathy (TO) is most prevalent among females in the fourth and fifth decades and is usually associated with thyroid dysfunction. Thyroid-associated orbitopathy may precede, coincide, or follow the systemic complications of dysthyroidism. The ocular manifestations of thyroid-associated orbitopathy include eyelid retraction, proptosis, chemosis, periorbital edema, and altered ocular motility with significant functional, social, and cosmetic consequences. we describe a unique case of unilateral exophthalmos in a young male patient. REPORT OF A CASE: A 30 year old male patient presented with unilateral axial proptosis left eye for 6 months with eye signs of thyroid disease and history of diplopia on up gaze, increased appetite, weight loss, excessive sweating. He also gave complaints of red, gritty, photophobic and watery eyes. His visual acuity was in the right eye 20/40 improving to 20/20 and in the left eye it was 20/40 improving to 20/20. Color vision was normal. There was no RAPD present, Eye signs included Von Graffe's sign (immobility or lagging of the upper eyelid on downward rotation of the eye), Stellwag's sign (infrequent or incomplete blinking), Dalrymple sign (widened palpebral fissure), Gifford sign (Difficulty everting the upper eyelids), Pochin's sign (blinking rate is reduced), Rosenbach's sign (unusual tremor of the eyelids), Snellen's sign (Bruit heard on auscultation over the eye), Mean's sign (increased superior scleral show on upgaze), Kocher's sign (staring and frightened appearance), Mobius' sign (inability to maintain convergence of the eyes), Suker's sign (fixation becomes difficult in extreme lateral gaze). The intraocular pressure in the RE was 17 mm Hg and LE was 19 mm of Hg. There was restriction of movements in the upgaze in the left eye. There was no corneal involvement. The visual fields were normal. Serum T3, T4 were normal with elevated TSH levels, B-scan showed thickened muscle belly of inferior rectus muscle. On CT scan Proptosis of the left eye noted (the distance from the interzygomatic line to anterior aspect of globe is 28 mm), Increase in both intra and extraconal fat is noted in the left eye , Increase in the size and altered signal intensity is noted in the muscle belly of inferior rectus of left eye with sparing of the tendon. On histologic examination Fibrosis with degenerative changes in the eye muscles, Lymphocytic cell infiltration, Accumulation of mucopolysaccharides, interstitial edema with increased collagen production was seen. The patient was treated conservatively with maintenance of euthyroid

Degeneration of the Brainstem

Magnetic resonance imaging (MRI) is the most sensitive imaging technique for assessing brainstem involvement in neurodegenerative diseases. An MRI can assess the degree of atrophy of the brainstem and alterations in signal intensity on T2-weighted images in the affected areas, which are the main imaging findings found in these diseases. Besides, diffusion-weighted MRI and proton MR spectroscopy are tools that play an important role in the characterization of these entities. Our purpose is to describe the neurodegenerative diseases that predominantly affect the brainstem highlighting the imaging findings most useful for diagnosis.

Bilateral External Ophthalmoplegia in Biotin-Responsive Basal Ganglia Disease

A 10-year-old girl with a 4-month history of abnormal gait and dysarthria was admitted to the hospital with altered mental status that had progressed over the previous 3 days in the context of febrile illness. The patient's family reported that she did not use drugs, and the family history is remarkable only for consanguinity. On physical examination, she was confused, having generalized dystonia and bilateral external ophthalmoplegia, and she was anarthric. The results of toxicologic and autoimmune, cerebrospinal fluid, thyroid, bacterial and viral, and metabolic studies, including tandem mass spectrometry, urine for organic acids, and levels of lactic acid, ammonia, acylcarnitines, copper, ceruloplasmin, biotin, and thiamine, were all negative. An initial magnetic resonance imaging (MRI) of the brain showed abnormal signal intensity alterations bilaterally involving the cerebellum, basal ganglia, medial nucleus of the thalamus with a characteristic “bat-wing” appearance, and cerebral cortex (Figure). The affected areas showed increased signal consistent with vasogenic edema on diffusion-weighted images and apparent diffusion coefficient map (not shown). The MRI findings suggested biotin-responsive basal ganglia disease. Sequencing of the SLC19A3 gene identified a pathogenic homozygous mutation c.1264A>G (p.Thr422Ala). The patient was administered thiamine and biotin, achieving marked improvement in her confusion, extraocular movements, and ambulation during the next 4 days. Three months later, she exhibited only mild dysarthria. Repeated brain MRI showed resolution of the vasogenic edema with residual atrophy and gliosis in the basal ganglia (Figure). The physical exam finding of acute to subacute, bilateral external ophthalmoplegia is telling for an energy breakdown, as occurs with biotin-responsive basal ganglia disease, thiamine deficiency, and mitochondrial defects. That exam finding would lead one to examine the midbrain, thalamus, and basal ganglia on brain MRI. Biotin-responsive basal ganglia disease is an autosomal recessive, underdiagnosed pan-ethnic treatable condition, related to thiamine transporter-2 deficiency. It needs to be included in the differential diagnosis for unexplained acute dystonia, bilateral external ophthalmoplegia and encephalopathy, and neuroimaging showing vasogenic edema in the bilateral putamen and caudate nuclei, infratentorial and supratentorial cortex, and brainstem, because a therapeutic trial with thiamine and biotin can be lifesaving.1Ozand P.T. Gascon G.G. Al Essa M. Joshi S. Al Jishi E. Bakheet S. et al.Biotin-responsive basal ganglia disease: a novel entity.Brain. 1998; 121: 1267-1279Crossref PubMed Scopus (136) Google Scholar, 2Serrano M. Rebollo M. Depienne C. Rastetter A. Fernández-Álvarez E. Muchart J. et al.Reversible generalized dystonia and encephalopathy from thiamine transporter 2 deficiency.Mov Disord. 2012; 27: 1295-1298Crossref PubMed Scopus (35) Google Scholar

Case of Atypical Wernicke's Encephalopathy in a GB Cancer Patient

Wernicke’s encephalopathy (WE) is an acute neuropsychiatric syndrome resulting from thiamine deficiency. Traditionally, diagnosis of WE rests on a clinical symptom triad consisting of ocular signs, altered consciousness, and ataxia. However, the complete triad is only present in a fraction of cases, which means that WE tends to be under-diagnosed, especially in nonalcoholic patients. Brain MRI of WE patients usually shows symmetrical signal intensity alterations in the thalami, mammillary bodies, and periaqueductal area, because of cytotoxic edema in the same region. These typical findings are useful diagnostic leads in WE patients with atypical symptoms. However, atypical findings can occasionally be seen in the vermis of cerebellum and cerebellar nuclei. Notably, alterations of signal intensity in the cerebellar dentate nuclei, which is a typical finding of metronidazole-induced encephalopathy (MIE), need to be distinguished according to medication history and response to thiamine. (Korean J Med 2013;84:602-607)

"Severe Neurological Deficit" a Rare Complication Following Spinal Anesthesia

Severe neurological deficit following spinal anesthesia is an uncommon incident. Here we report a 24-year-old female who was given spinal anesthesia for lower segment caesarean section developed transient severe pain at the site of needle insertion radiating to right lower limb during the procedure followed by weakness predominantly involving the right lower limb and areflexia. Her magnetic resonance imaging of spine revealed signal intensity alteration in the spinal cord from 5th thoracic segment to the conus suggestive of extensive myelitis along with involvement of nerve roots following the procedure. doi: http://dx.doi.org/10.4021/jnr140w

Rydberg and ion-pair states of HBr: New REMPI observations and analysis

Two-dimensional REMPI data, obtained by recording ion mass spectra for HBr as a function of two-photon wavenumber, revealed previously unobserved (2+n) REMPI spectra for H79Br and H81Br. Spectra were assigned and analyzed to derive band origins and rotational parameters of Rydberg and ion-pair states. Perturbation effects, showing as line-shifts and/or signal intensity alterations, were found to be helpful in spectra assignments.

Assessment of the apparent diffusion coefficient (ADC) of normal breast tissue during the menstrual cycle at 3T using image segmentation

Diffusion weighted imaging (DWI) is quantitative MRI technique that generates an image contrast based on the intrinsic random motion properties of water molecules within tissue, known as Brownian motion. It is able to detect any physiological abnormality at the cellular level and the assessment of the change can be visually (qualitative) assessed by observing the alteration in signal intensity (SI) and also can be quantitatively assessed by calculating the apparent diffusion coefficient (ADC) value which reflects the diffusion rate of water molecules [1]. Based on histological studies the menstrual cycle is divided into four phases (weeks): menstrual (week 1), follicular (week 2), ovulation (week 3), and luteal (week 4). The morphologic changes occur in stromal and epithelial tissues due to the rise and fall of oestrogen and progesterone levels and were first described by Rosenberg [2]. The mammary epithelium changes from small cuboidal cells in the first half of the cycle to tall, columnar, well differentiated cells in the second half of the cycle. The follicular phase is characterized by the gradual increase in oestrogen levels which peak at ovulation. During this phase the glandular lumen is poorly defined and contains minimal secretions. The intralobular tissue is characterized by dense stroma and more collagenous tissue with less cell density. However, during the luteal phase the secretion of progesterone hormone increases and peaks leading to greater proliferative and mitotic activity of the mammary epithelium resulting in enlarged lobules which become more rounded with active secretion into the lumen. The intralobular stroma becomes distinctly loose due to the accumulation of oedema [3]. Several MRI studies have been performed demonstrating that the vascularity of the breast parenchymal tissue changes during

Radiological features of Gorham’s disease

To describe the key findings on plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI) of Gorham's disease. Eight children diagnosed with Gorham's disease between 1999 and 2009 were included. All imaging studies performed on each patient were reviewed with special attention to the extent of bone, soft tissue, and visceral involvement. All patients had bone lesions at diagnosis, most commonly in the vertebrae. CT showed generalized osteopenia, multiple lytic lesions, and heterogeneous bone density. MRI demonstrated altered signal intensity in bone marrow that was hyperintense on T1 imaging. Seven patients had soft-tissue lymphangiomatous lesions adjacent to identified osseous lesions. Four patients had chylous pleural effusions: three with bilateral and one with unilateral involvement. The spleen was involved in six patients. Splenic lesions and soft-tissue involvement are common in patients with Gorham's disease. The presence of extra-osseous lesions along with characteristic bone lesions on plain radiography may be pathognomonic of Gorham's disease.

Rathke’s cleft cyst with non-hemorrhagic rupture resulting in alteration of signal intensity for a short period: case report.

In a case of 23-year-old female with Rathke's cleft cyst (RCC), unusual changes with size and morphology on computed tomography (CT) and magnetic resonance images (MRI) were noted in a short period of 3 weeks after spontaneous rupture. The CT noted that the intracystic isodensity was changed to hyperdensity. And MRI showed not only a decrease in size of the lesion but also changing from hypo- and hyperintensity in T1- and T2-weighted images to hyperintensity in both T1- and T2-weighted images. The intraoperative findings disclosed that the cyst content was milky-like, but not hemorrhagic. We considered that the leakage of cyst content to the cerebrospinal fluid pathway caused not only inflammatory reaction but also waxing and waning of both the cyst size and intralesional protein concentration, which resulted in unusual changing CT and MR appearance. We should take into consideration that the nature of RCC can be altered by not only intracystic hemorrhage but also non-hemorrhagic rupture even for a short period.

Subacute Progressive Ascending Myelopathy from L2 to C4 after A Burst Fracture of the Second Lumbar Vertebra

Subacute progressive ascending myelopathy is a rare, poorly understood neurological complication of spinal cord injury, unrelated to mechanical compression, instability, or syrinx formation at the level of injury or above. To date, there is no known treatment for this dramatic spinal cord injury complication. We present a case of subacute progressive myelopathy after lumbar spine trauma. The therapy consisted of plasmapheresis, hyperbaric oxygen, high-dose cortisol, antibiotic, and antiviral drugs. At 1 year post injury, the patient had recovered most of his lost upper-extremity function and MRI demonstrated only discrete signal intensity alterations extending to T3/4.

“Severe Neurological Deficit” a Rare Complication Following Spinal Anesthesia

Severe neurological deficit following spinal anesthesia is an uncommon incident. Here we report a 24-year-old female who was given spinal anesthesia for lower segment caesarean section developed transient severe pain at the site of needle insertion radiating to right lower limb during the procedure followed by weakness predominantly involving the right lower limb and areflexia. Her magnetic resonance imaging of spine revealed signal intensity alteration in the spinal cord from 5th thoracic segment to the conus suggestive of extensive myelitis along with involvement of nerve roots following the procedure. J Neurol Res. 2012;2(5):221-223 doi: https://doi.org/10.4021/jnr140w

Investigation by Imaging Mass Spectrometry of Biomarker Candidates for Aging in the Hair Cortex

BackgroundHuman hair is one of the essential components that define appearance and is a useful source of samples for non-invasive biomonitoring. We describe a novel application of imaging mass spectrometry (IMS) of hair biomolecules for advanced molecular characterization and a better understanding of hair aging. As a cosmetic and biomedical application, molecules whose levels in hair altered with aging were comprehensively investigated.MethodsHuman hair was collected from 15 young (20±5 years old) and 15 older (50±5 years old) volunteers. Matrix-free laser desorption/ionization IMS was used to visualize molecular distribution in the hair sections. Hair-specific ions displaying a significant difference in the intensities between the 2 age groups were extracted as candidate markers for aging. Tissue localization of the molecules and alterations in their levels in the cortex and medulla in the young and old groups were determined.ResultsAmong the 31 molecules detected specifically in hair sections, 2—one at m/z 153.00, tentatively assigned to be dihydrouracil, and the other at m/z 207.04, identified to be 3,4-dihydroxymandelic acid (DHMA)—exhibited a higher signal intensity in the young group than in the old, and 1 molecule at m/z 164.00, presumed to be O-phosphoethanolamine, displayed a higher intensity in the old group. Among the 3, putative O-phosphoethanolamine showed a cortex-specific distribution. The 3 molecules in cortex presented the same pattern of alteration in signal intensity with aging, whereas those in medulla did not exhibit significant alteration.ConclusionThree molecules whose levels in hair altered with age were extracted. While they are all possible markers for aging, putative dihydrouracil and DHMA, are also suspected to play a role in maintaining hair properties and could be targets for cosmetic supplementation. Mapping of ion localization in hair by IMS is a powerful method to extract biomolecules in specified regions and determine their tissue distribution.

Partial achilles tendon rupture presenting with giant hematoma; MRI findings of 4 year follow up

In the young population, spontaneous rupture of Achilles tendon is very rare. The big hematoma is also rare finding of the Achilles tendon partial rupture. It is usually seen with complete rupture. We presented imaging findings of 4 years follow up of the spontaneous partial rupture of Achilles tendon presenting with giant expanding hematoma and mimicking complete rupture radiologically. We discussed the alterations of tendon signal intensity and result of conservative therapy after partial rupture with big hematoma in the long term. A 29 year-old man, applied with pain and swelling in the retrocalcaneal region of left ankle. He did not have chronic metabolic disease. He was not active in physical activities. X-ray radiograms were normal. At magnetic resonance images (MRI), there was an intratendinous big hematoma, subcutanous fat planes were edematous around tendon. The diagnosis was partial rupture and giant hematoma. Hematoma was drained. The conservative treatment was applied and his complaints disappeared. After treatment, approximately 4 years later, control MRI showed thickened and hypointense tendon in all images.

Is galectin-1 a trigger for trophoblast cell fusion?: the MAP-kinase pathway and syncytium formation in trophoblast tumour cells BeWo

Galectin-1 (gal-1), a member of the mammalian β-galactoside-binding proteins, exerts biological effects by recognition of glycan ligands, including those involved in cell adhesion and growth regulation. In a previous study, we demonstrated that gal-1 induces cell differentiation processes on the membrane of choriocarcinoma cells BeWo, including the receptor tyrosine kinases, REarranged during transfection, janus kinase 2 and vascular endothelial growth factor receptor 3. Within this study, we examined which mitogen-activated protein kinases (MAPK) and serine/threonine kinases were phoshorylated by gal-1. Out of a number of 21 different MAPKs and other serine/threonine kinases, the stimulation of BeWo cells with gal-1 showed a significant alteration of signal intensity in extracellular-regulated kinases 1/2 (ERK1/2), Akt-3, Akt-pan and glycogen synthase kinase-α/β (GSK-3α/β). We demonstrated that gal-1 significantly inhibited ERK1/2, Akt-3/pan and GSK-3α/β phosphorylation in BeWo cells and in addition induced Elk1 transcription factor activation. In contrast to gal-1 effects, MAPK inhibitor U0126 reduced syncytium formation of BeWo cells. The results of our data showed that phosphorylation of MAP kinases are involved in gal-1-induced signal transduction processes in BeWo cells. Additional results obtained with MAPK inhibitor U0126 close the gap between syncytium formation induced by gal-1 and MAPK activation in trophoblast cells. Furthermore, we demonstrated that gal-1 induces the activation of Elk1, a transcription factor that is activated by MAPK pathways.